Don't know how to get a message

Are you sure that the person who sent you a message had the right number? Double check that by getting the person to ring them number they sent it to and see if your phone rings.

Sometimes messages can get delayed in the tranmission system, or sometimes they can error from the sender’s end (they would get a message to say it had). If neither of these seem likely, I.e. it has been a good amount of time since they sent it and they got no message to say sending had failed, then contact your phone network provider and they should be able to sort it. After all, you pay them regularly enough via contract or pay as you go, so they should provide a service in exchange for this money. Taking your handset into the place you bought it from might also help as they will be able to show you if you are going wrong somewhere or exchange the phone if faulty.